The present invention relates to a fuel injection equipment of a direct injection type internal combustion engine provided with an injector, which jets a fuel directly into a combustion chamber, and a control unit therefor.
Vehicles (automobiles) are presently demanded of reduction in emission such as CO, HC, NOx, etc. contained in exhaust gases of automobiles and reduction in fuel consumption from a standpoint of environmental preservation. With a view to reduction in them, direct injection type internal combustion engines have been developed. With direct injection type internal combustion engines, an injector jets a fuel directly into a combustion chamber of a cylinder whereby reduction in emission, reduction in fuel consumption, an improvement in engine output, etc. are accomplished.
There is particulate number of a particulate substance, so-called particulate matter (referred below to as PM) as emission. The particulate number indicates a total particulate number of PM particles exhausted when a vehicle is operated in a predetermined operation pattern. In recent years, needs for reduction in particulate number of particulate matter are increasingly demanded to vehicular engines, in particular, direct injection type internal combustion engines.
It is known to split and jet a fuel quantity, which is needed in a direct injection type internal combustion engine, plural times when the direct injection type internal combustion engine is operated, with a view to reduction in smoke, total hydro carbon, and the particulate number of particulate matter.
There have been proposed direct injection type internal combustion engines, for example, direct injection type internal combustion engines provided with injectors for direct injection of a fuel directly into cylinders, in which engines a fuel is jetted at least once in each of former, intermediate, and latter parts in intake stroke and respective fuel injection quantities are conformed to ratios of intake air flow rates per unit time in injection timings (JP-A-2007-177731).